Pre-tightening force measuring device

Abstract

The utility model belongs to the technical field of medical instruments, and provides a pre-tightening force measuring device which comprises a supporting frame. The driving assembly is movably arranged on the supporting frame; one end of the force measuring assembly is connected with the driving assembly through a connecting piece; the traction assembly is connected with the other end of the force measuring assembly, and the end, deviating from the force measuring assembly, of the traction assembly is used for abutting against the flexible wire; the driving assembly is configured to drive the force measuring assembly and the traction assembly to move so as to enable the flexible wire to deform; the scale mark is arranged between the driving assembly and the supporting frame and is configured to measure the distance value of the flexible wire driven by the traction assembly to move so as to calculate the initial pre-tightening force of the flexible wire through the distance value and the force value output by the force measuring assembly. The setting of the scale marks not only can quickly and accurately obtain the moving distance value of the flexible wire, but also can obtain multiple groups of force values and distance values in the measurement process, thereby providing verification for the calculated initial pre-tightening force, and enabling the measured initial pre-tightening force result to be more accurate.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to a preload force measuring device. Background Art

[0002] In the end instruments of laparoscopic surgical robots, most of the instruments use the wire transmission method to transmit the rotation of the motor in the instrument box to the end instrument opening, closing, clamping and other movements. However, in the wire transmission, it is necessary to study the transmission error, transmission backlash, transmission stiffness, coupling and other characteristics to improve the overall performance of the instrument, and most of these characteristics are related to the wire transmission preload. Generally, a certain preload (given initial value) is applied during the instrument assembly process, but as the instrument is used, the preload of the instrument will change due to the deformation of the structural parts, assembly clearance, transmission wear, and creep characteristics of the wire, including stress relaxation. How to detect the preload of the instrument in real time is a very critical factor in determining the service life of the instrument.

[0003] The instrument box of the end instrument is small in size, has many transmission wires, and the preload force generally does not exceed 3kg. Therefore, how to conveniently, timely and accurately detect the preload force of several transmission wires without disassembling the instrument box is a difficulty in the design of preload tooling. Utility Model Content

[0004] The embodiment of the present application provides a preload force measuring device, which can quickly and accurately obtain the distance value of the flexible wire movement, thereby facilitating the rapid and accurate calculation of the initial preload force of the flexible wire.

[0005] The embodiment of the present application provides a preload force measuring device for measuring the preload force of a flexible wire, comprising:

[0006] Support frame;

[0007] A driving assembly, movably disposed on the support frame;

[0008] A force measuring assembly, one end of which is connected to the driving assembly via a connecting piece;

[0009] a pulling assembly connected to the other end of the force measuring assembly, wherein the end of the pulling assembly facing away from the force measuring assembly is used to abut against the flexible wire; the driving assembly is configured to drive the force measuring assembly and the pulling assembly to move so as to deform the flexible wire;

[0010] The scale mark is arranged between the driving assembly and the supporting frame, and is configured to measure the distance value that the pulling assembly drives the flexible wire to move, so as to calculate the initial preload force of the flexible wire through the distance value and the force value output by the force measuring assembly.

[0011] In a feasible implementation, the scale mark includes a first mark and a second mark, the first mark is set on the support frame, the second mark is set on the driving component, and the sum of the numerical value of the first mark and the numerical value of the second mark is the distance value.

[0012] In a feasible implementation, the support frame includes a fixed sleeve, and the outer side wall of the fixed sleeve is provided with the first mark;

[0013] The driving assembly includes a differential cylinder, the differential cylinder cover is arranged on the fixed sleeve, and the second mark is arranged at the end of the differential cylinder.

[0014] In a feasible implementation, the driving assembly further includes an adjusting knob and a rotating threaded shaft, the adjusting knob and the rotating threaded shaft are fixedly connected, the rotating threaded shaft is passed through the fixed sleeve and is threadedly connected to the fixed sleeve;

[0015] The differential cylinder is clamped on the rotating threaded shaft and moves along with the movement of the rotating threaded shaft.

[0016] In a feasible implementation, the drive assembly further includes a locking nut, which is disposed between the adjusting knob and the rotating threaded shaft, and between the adjusting knob and the differential cylinder.

[0017] In a feasible implementation, the connecting member includes an adapter fixing sleeve and a connecting bearing, and the connecting bearing is arranged on the adapter fixing sleeve. One of the rotating threaded shaft and the force measuring component is connected to the adapter fixing sleeve, and the other is connected to the connecting bearing, so that the force measuring component is limited in the axial direction of the rotating threaded shaft.

[0018] In a feasible implementation, the connecting bearing is an externally threaded bearing;

[0019] The end of the rotating threaded shaft is clamped with the adapter fixing sleeve, one end of the external threaded bearing is fixed in the adapter fixing sleeve, and the other end extends out of the adapter fixing sleeve and is fixedly connected to the force measuring component.

[0020] In a feasible implementation, the side wall of the fixed sleeve is configured with at least one guide channel, and part of the force measuring assembly is embedded in the guide channel;

[0021] And / or, the force measuring component is a tension sensor or a pressure sensor.

[0022] In a feasible implementation, the support frame also includes support rods arranged on both sides of the fixed sleeve, and adjustment wheels movably mounted on the support rods, the two adjustment wheels are used to contact the flexible wire, and the two adjustment wheels are symmetrically arranged about the pulling assembly.

[0023] In a feasible implementation, the pulling assembly includes a pulling rod and a movable guide wheel, and the movable guide wheel and the adjusting wheel are respectively located on two sides of the flexible wire.

[0024] In a feasible implementation, the pulling assembly further includes a guide wheel shaft, and the guide wheel shaft detachably sets the movable guide wheel at the end of the pulling rod;

[0025] And / or, the pulling assembly is connected to the force measuring assembly via a fixed adapter.

[0026] The preload force measurement device provided in the embodiment of the present application provides support for the driving component, the force measuring component and the pulling component through a support frame, so that during the measurement process, the driving component drives the force measuring component, the force measuring component drives the pulling component, and the pulling component drives the flexible wire to deform. When the force value is obtained through the force measuring component, the distance value of the flexible wire movement can also be directly read through the scale mark set between the driving component and the support frame to calculate the initial preload force of the flexible wire. The setting of the scale mark can not only quickly and accurately obtain the distance value of the flexible wire movement, but also obtain multiple groups of force values ​​and distance values ​​during the measurement process, thereby providing verification for the calculated initial preload force, so that the measured initial preload force result is more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the drawings required for use in the embodiments or the related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 is a schematic diagram of the structure of the end device provided according to an embodiment of the present application;

[0029] Figure 2 is a schematic diagram of the overall structure of a preload force measurement device provided according to an embodiment of the present application;

[0030] Figure 3 This is one of the disassembled structural schematic diagrams of the preload force measurement device provided in the embodiment of the present application;

[0031] Figure 4 This is a second schematic diagram of the disassembled structure of the preload force measurement device provided in an embodiment of the present application;

[0032] Figure 5 is a schematic diagram of force analysis of a flexible wire provided according to an embodiment of the present application;

[0033] Figure 6 is a schematic diagram of actual measurement of a measuring device provided in an embodiment of the present application;

[0034] Figure 7 is a schematic cross-sectional structural diagram of a preload force measurement device provided in an embodiment of the present application at one viewing angle;

[0035] Figure 8 yes Figure 7 A schematic diagram of the structure enlargement at the center A;

[0036] Fig. 9 is a schematic cross-sectional structural diagram of the preload force measurement device provided in an embodiment of the present application from another perspective;

[0037] Fig.10 It is a schematic diagram of the calibration structure of the measuring device provided according to an embodiment of the present application.

[0038] Reference numerals:

[0039] 11. Clamp head rotation axis; 12. Wrist joint rotation axis; 13. Flexible rope; 14. Wrist joint; 15. Instrument front end; 16. Instrument box;

[0040] 21. Support plate; 22. Fixed pulley; 23. Weight;

[0041] 100, support frame; 110, fixed sleeve; 111, guide channel; 120, support rod; 130, adjustment wheel;

[0042] 200, driving assembly; 210, adjusting knob; 220, rotating threaded shaft; 230, differential cylinder; 240, locking nut;

[0043] 400, force measuring assembly;

[0044] 300, connecting piece; 310, adapter fixing sleeve; 320, connecting bearing;

[0045] 500, pulling assembly; 510, pulling rod; 520, moving guide wheel; 530, guide wheel shaft;

[0046] 600, scale mark; 610, first mark; 620, second mark;

[0047] 700. Fixed adapter. DETAILED DESCRIPTION

[0048] The following is a further detailed description of the implementation of the present application in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application but cannot be used to limit the scope of the present application.

[0049] In the description of the embodiments of the present application, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0050] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0051] In the embodiments of the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0052] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0053] Before introducing the preload force measuring device of the embodiment of the present application, the application scenario of the preload force measuring device is explained first. The preload force measuring device of the present application can be applied to the end instrument of a laparoscopic surgical robot. The end instrument usually has four degrees of freedom, including rotation, pitch, yaw, and opening and closing of the end clamping of the instrument. Except for the rotation degree of freedom which is realized by gear transmission in the instrument box, the other degrees of freedom are transmitted to the end instrument by wire transmission to transmit the shaft movement in the instrument. Figure 1 is a schematic diagram of the structure of the end device provided according to an embodiment of the present application, such as Figure 1 The schematic diagram of the device structure shown in the figure shows that the device box 16 includes a pair of forceps head rotation shafts 11 for controlling the opening and closing of the front end 15 of the device. A wrist joint rotation shaft 12 controls the movement of the wrist joint 14. Figure 1 It includes a flexible transmission wire rope 13, Figure 1 The flexible rope 13 in the apparatus has three pairs (also referred to as flexible wires).

[0054] During the assembly process of the instrument, it is necessary to apply pre-tightening force to the three pairs of flexible ropes 13 to improve the overall stiffness of the instrument, reduce the wire transmission error and its backlash error, thereby improving the transmission accuracy of the instrument. The pre-tightening force can be applied through a dedicated pre-tightening force applying device. During the initial assembly of the instrument, an initial pre-tightening force is applied to the flexible wire according to a fixed torque or tension. For this type of transmission of the instrument, the pre-tightening force is generally less than 3kg. Excessive pre-tightening force will increase the wear of the instrument, thereby reducing the service life of the instrument.

[0055] Due to the precise structure of surgical robot instruments, every 1 mm of wire transmission will cause a large swing of the end forceps head. In addition, during the use of the instrument, the wear of the flexible wire and the deformation of the structural parts will affect the overall performance of the instrument. Therefore, how to detect the change in the preload force of the instrument after a period of use without disassembling the entire instrument as a standard for detecting the performance of the instrument will be more helpful in determining whether the initial preload force of the instrument is appropriate and the impact of the preload force on the service life of the instrument.

[0056] Based on the above problems, the present application provides a preload force measuring device for measuring the preload force of a flexible wire. Figure 2 is a schematic diagram of the overall structure of a preload force measurement device provided according to an embodiment of the present application; Figure 3 This is one of the disassembled structural schematic diagrams of the preload force measurement device provided in the embodiment of the present application; Figure 4 This is a second schematic diagram of the disassembled structure of the preload force measurement device provided in the embodiment of the present application. Figure 2-4As shown, the preload force measuring device may include a support frame 100 , a driving assembly 200 , a force measuring assembly 400 , a pulling assembly 500 and a scale mark 600 .

[0057] The driving component 200 is movably arranged on the support frame 100; one end of the force measuring component 400 is connected to the driving component 200 through the connecting piece 300; the pulling component 500 is connected to the other end of the force measuring component 400, and the end of the pulling component 500 facing away from the force measuring component 400 is used to abut against the flexible wire; the driving component 200 is configured to drive the force measuring component 400 and the pulling component 500 to move so as to deform the flexible wire; the scale mark 600 is arranged between the driving component 200 and the support frame 100, and is configured to measure the distance value that the pulling component 500 drives the flexible wire to move, so as to calculate the initial preload force of the flexible wire through the distance value and the force value output by the force measuring component 400.

[0058] It can be understood that the support frame 100 can provide support for the entire preload force measuring device (hereinafter referred to as the measuring device). The support frame 100 can be provided with a supporting plate to stably place the measuring device on the end device, thereby achieving effective abutment between the pulling component 500 and the flexible wire, and can effectively avoid the measurement accuracy being affected by external factors such as the weight of the measuring device itself during the initial stage of measurement and the measurement process.

[0059] In order to calculate the initial preload force F0 of the flexible wire, it is necessary to obtain the force value of the flexible wire under the pulling component 500, and the deformation distance corresponding to the force value. More specifically, the pulling component 500 can pull the flexible wire in the direction toward the driving component 200, or press the flexible wire in the direction away from the driving component 200. No matter which of the above methods is used, the flexible wire will be deformed, that is, the length of the flexible wire will be lengthened. The specific operation process can be that the driving component 200 is driven to move by an external force (manually), the driving component 200 then drives the force measuring component 400 to move, the force measuring component 400 drives the pulling component 500 to move, and the pulling component 500 finally drives the flexible wire abutting therewith to move. Since the connection stability of the driving component 200, the force measuring component 400 and the pulling component 500 is relatively high, the moving distance of the three is the movement amount of the flexible wire abutment point.

[0060] The tension or pressure on the flexible wire can be obtained by the force measuring component 400. In one example, the force measuring component 400 is a tension sensor or a pressure sensor. Specifically, the force sensor can transmit the force value to the display device in real time so that the staff can obtain it. The force value directly obtained by the sensor during the measurement process can be called the sensor force value F s The tension on the flexible wire after being stretched can be called the flexible wire tension F0'.

[0061] In order to obtain the length difference of the flexible wire during the deformation process, it is first necessary to obtain the distance (horizontal distance) between the two unchanged end points of the flexible wire during the deformation process. This distance can be the distance between the wire wheels wound at both ends of the flexible wire. Of course, in order to increase the accuracy of the measurement, two static guide wheels symmetrical about the pulling component 500 can be set on the support frame 100. The two static guide wheels can contact the flexible wire, and in the initial stage of measurement, that is, the measuring device is installed on the flexible wire but before the measurement, the contact point between the static guide wheel and the flexible wire and the contact point between the pulling component 500 and the flexible wire are in a straight line. The distance L between the two static guide wheels can be known in advance, and combined with the lifting distance of the pulling component 500, the length L' of the flexible wire after being stretched can be calculated.

[0062] More specifically, a moving guide wheel 520 can be provided at the end of the pulling assembly 500 to reduce the friction force of pulling or pressing the flexible wire. Taking the pulling flexible wire as an example, during installation, the moving guide wheel 520 of the pulling assembly 500 can be removed so that the flexible wire can be inserted into the pulling assembly 500, thereby contacting the upper surface of the moving guide wheel 520, and the static guide wheels located on both sides of the dynamic guide wheel 520 can directly contact the flexible wire, that is, the flexible wire contacts the lower surface of the static guide wheel. During the measurement process, the driving assembly 200 applies force to drive the force measuring assembly 400 and the pulling assembly 500 (moving guide wheel 520) to move up in turn, and then the flexible wire also moves up with the moving guide wheel 520. Since the static guide wheel is relatively stationary relative to the support frame 100, the force direction of the part of the flexible wire located between the static guide wheel and the moving guide wheel 520 can be changed, and the flexible wire tensioning force F0' exerted on the flexible wire at this time can be calculated by subsequent force analysis.

[0063] In addition, in order to calculate the deformation length difference △L of the flexible wire, L' also needs to be calculated based on the upward movement distance b of the flexible wire. In order to quickly and accurately obtain the upward movement distance b of the flexible wire, that is, the upward movement distance of the driving component 200, the force measuring component 400 and the pulling component, it can be directly read by the scale mark 600 set between the driving component 200 and the support frame 100. For example, the scale mark 600 between the driving component 200 and the support frame 100 can be set in the style of a vernier caliper. When the driving component 200 moves up or down relative to the support frame 100, the distance it moves can be obtained by reading, and then the upward movement distance b is obtained.

[0064] Of course, the scale mark 600 between the drive assembly 200 and the support frame 100 can also be set in the style of a micrometer, and the drive assembly 200 can be threadedly connected to the support frame 100. The process of the drive assembly 200 rotating relative to the support frame 100 is the process of the drive assembly 200 driving the force measuring assembly 400 and the pulling assembly 500 to move up or down. In order to prevent the drive assembly 200 from driving the pulling assembly 500 to rotate, thereby wrapping the flexible wire around the pulling assembly 500, this embodiment sets a connector 300 between the drive assembly 200 and the force measuring assembly 400, so as to limit the force measuring assembly 400 and the pulling assembly 500 to move only in the linear direction. The specific structure of the connector 300 can be understood with reference to the following content.

[0065] According to the known data and the data obtained by the measuring device, the following table is shown:

[0066]

[0067] Figure 5 is a schematic diagram of the force analysis of the flexible wire provided in the embodiment of the present application, and combined with Figure 5 As shown, the calculation process of the initial preload force F0 of the flexible wire is:

[0068] Calculate the angle θ between the flexible wire and the vertical direction in the stretched state,

[0069] θ=arctan(0.5L / b) (1)

[0070] Known sensor force value F s The flexible wire tension F0' can be calculated based on the θ value obtained from formula (1).

[0071]

[0072] Knowing the distance L between the two static guide wheels, the length of the flexible wire after being stretched can be calculated according to the value of θ obtained by formula (1):

[0073] L',

[0074]

[0075] Then, the deformation length difference of the flexible wire △L=2L'-L,

[0076]

[0077] Calculate the force difference △F before and after the flexible wire is stretched.

[0078]

[0079] Wherein, k is the stiffness coefficient of the flexible wire, which can be measured in advance by a tensile test device.

[0080] Finally, the calculation result of the initial preload force F0 of the flexible wire is obtained by subtracting formula (5) from formula (2).

[0081]

[0082] The present application sets scale marks 600 on the drive assembly 200 and the support frame 100. On the one hand, it is for quick and accurate reading to obtain the moving distance b of the flexible wire along the vertical direction. On the other hand, it can achieve multiple sets of moving distances and their corresponding sensor force values ​​in one measurement. By calculating the initial preload of the flexible wire multiple times, the accuracy of the calculation can be guaranteed, and a more accurate initial preload can be obtained by taking the average value.

[0083] It should be noted that when the deformation data of the flexible wire is obtained by the measuring device, the range of movement of the flexible wire in the vertical direction can be determined in combination with the measurement range of the sensor used and the elastic stiffness of the flexible wire, so as to avoid the situation where the flexible wire exceeds the measurement range of the sensor when the deformation amount is large, resulting in inaccurate measurement, or excessive deformation force is applied to the flexible wire, resulting in damage to the flexible wire.

[0084] In the present application, the support frame 100 is used to provide support for the driving component 200, the force measuring component 400 and the pulling component 500, so that during the measurement process, the driving component 200 drives the force measuring component 400, the force measuring component 400 drives the pulling component 500, and the pulling component 500 drives the flexible wire to deform. When the force value is obtained by the force measuring component 400, the distance value of the flexible wire movement can also be directly read through the scale mark 600 set between the driving component 200 and the support frame 100 to calculate the initial preload force of the flexible wire. The setting of the scale mark 600 can not only quickly and accurately obtain the distance value of the flexible wire movement, but also obtain multiple groups of force values ​​and distance values ​​during the measurement process, thereby providing verification for the calculated initial preload force, so that the measured initial preload force result is more accurate.

[0085] Next, we will combine the attached Figure 2-Figure 9 The specific structure of the preload force measuring device in the embodiment of the present application is described in detail.

[0086] like Figure 3 and Figure 4 As shown, in some embodiments, the scale mark 600 includes a first mark 610 and a second mark 620, the first mark 610 is set on the support frame 100, and the second mark 620 is set on the driving assembly 200, and the sum of the numerical value of the first mark 610 and the numerical value of the second mark 620 is the distance value.

[0087] It can be understood that the first mark 610 is a fixed scale set on the support frame 100, and the second mark 620 is a movable scale set on the drive assembly 200, which can be understood with reference to a vernier caliper or a micrometer. Taking a micrometer as an example, during the measurement process, when the drive assembly 200 rotates relative to the support frame 100, it can move up or down relative to the support frame 100, and the relative position of the second mark 620 and the first mark 610 will also change. However, no matter how the two change, when the measurement stops, the value of the first mark 610 can be read first, and then the value of the second mark 620 can be read to finally obtain a reading result accurate to the thousandth of a millimeter. Not only is the reading convenient, but the result is accurate, which is conducive to the subsequent calculation of a more accurate initial preload of the flexible wire, and is more helpful to determine whether the initial preload size of the device is appropriate, and the influence of the preload size on the service life of the device.

[0088] Specifically, the first identifier 610 and the second identifier 620 are set as follows: Figure 3 and Figure 4 As shown, in some embodiments, the support frame 100 includes a fixed sleeve 110, and the outer wall of the fixed sleeve 110 is provided with a first mark 610; the driving assembly 200 includes a differential cylinder 230, the differential cylinder 230 is covered on the fixed sleeve 110, and the end of the differential cylinder 230 is provided with a second mark 620.

[0089] It is understandable that the connection between the fixed sleeve 110 and the differential cylinder 230 can be a threaded connection (similar to a micrometer) or a sliding connection (similar to a vernier caliper). If it is a sliding connection, one way that can be thought of is that the differential cylinder 230 is connected to the above-mentioned force measuring assembly 400 and the pulling assembly 500, so as to be able to drive the flexible wire to move in real time. The specific structure can be that a guide rail and a slider are provided between the differential cylinder 230 and the fixed sleeve 110, and the differential cylinder 230 can be moved downward relative to the fixed sleeve 110 by hand pressure. After moving a certain distance, the moving distance value of the flexible wire can be obtained by reading the first mark 610 and the second mark 620, and the sensor force value of the force measuring assembly 400 (pressure sensor) can also be obtained to finally calculate the initial preload force of the flexible wire.

[0090] The above method requires long-term hand pressure, which can easily lead to inaccurate readings due to shaking. Based on this, a locking member can be provided between the fixed sleeve 110 and the pulling assembly 500. The locking member can be a screw threadedly connected to the fixed sleeve 110. By turning the screw, the end of the screw can be abutted against the pulling assembly 500, thereby achieving relative fixation of the fixed sleeve 110 and the pulling assembly 500, which is convenient for reading. Of course, the locking member can also be a plurality of perforations provided on the pulling assembly 500, and a through hole provided on the fixed sleeve 110. By inserting a rod through one of the perforations, the relative fixation of the fixed sleeve 110 and the pulling assembly 500 can also be achieved. The specific structure of the locking member is not limited here.

[0091] In addition to the above-mentioned sliding connection method, a threaded connection can also be used. In some embodiments, the drive assembly 200 also includes an adjusting knob 210 and a rotating threaded shaft 220. The adjusting knob 210 and the rotating threaded shaft 220 are fixedly connected. The rotating threaded shaft 220 is passed through the fixed sleeve 110 and is threadedly connected to the fixed sleeve 110; the differential cylinder 230 is clamped on the rotating threaded shaft 220 and moves with the movement of the rotating threaded shaft 220.

[0092] Specifically, the adjustment knob 210 is located outside the fixed sleeve 110 for easy manual rotation. The rotating threaded shaft 220 is threadedly connected to the fixed sleeve 110. For example, the rotating threaded shaft 220 and the fixed sleeve 110 can be processed into a thread with a pitch of 0.5 mm. When the rotating thread is rotated in the fixed sleeve 110, it will move up or down relative to the fixed sleeve 110. Since the differential cylinder 230 is clamped on the rotating threaded shaft 220, the differential cylinder 230 can also move up or down relative to the fixed sleeve 110 while rotating. By adding the value of the first mark 610 and the value of the second mark 620, a reading result accurate to the thousandth of a millimeter is obtained, thereby realizing accurate measurement of the distance value of the flexible wire movement, so as to finally obtain a more accurate initial preload force of the flexible wire.

[0093] In order to enhance the connection firmness between the adjusting knob 210 and the rotating threaded shaft 220, and between the adjusting knob 210 and the differential cylinder 230, in some embodiments, the driving assembly 200 also includes a locking nut 240, which is disposed between the adjusting knob 210 and the rotating threaded shaft 220, and between the adjusting knob 210 and the differential cylinder 230.

[0094] It is understandable that by providing a locking nut 240 between the adjusting knob 210 and the rotating threaded shaft 220, the friction between the nut and the bolt is used for self-locking, so as to avoid the situation that the adjusting knob 210 and the rotating threaded shaft 220 are loose when the adjusting knob 210 is manually turned. In addition, at least one protrusion is provided on the outer ring of the rotating threaded shaft 220, and the protrusion can be engaged with the limiting groove in the differential barrel 230, so as to prevent the differential barrel 230 and the rotating threaded shaft 220 from rotating relative to each other.

[0095] In order to further enhance the firmness of the connection between the adjusting knob 210, the differential cylinder 230 and the rotating threaded shaft 220, a circle of bosses is constructed on the outer periphery of the rotating threaded shaft 220, and the bosses can form an annular groove with the lower end surface of the locking nut 240. The annular groove is used to accommodate the end of the differential cylinder 230. By clamping the locking nut 240, the differential cylinder 230 and the rotating threaded shaft 220 can be firmly connected, thereby ensuring the accuracy of measuring the moving distance of the flexible wire.

[0096] Figure 7 is a schematic cross-sectional structural diagram of a preload force measurement device provided in an embodiment of the present application at one viewing angle; Figure 8 yes Figure 7 A schematic diagram of the enlarged structure at point A in the middle.

[0097] like Figure 7 and Figure 8 As shown, in order to ensure that the rotating threaded shaft 220 does not affect the pulling of the flexible wire by the pulling assembly 500 below during the rotation process, it is avoided that the pulling assembly 500 rotates and drives the flexible wire to rotate. In some embodiments, the connecting member 300 includes an adapter fixing sleeve 310 and a connecting bearing 320, and the connecting bearing 320 is disposed in the adapter fixing sleeve 310. One of the force measuring assembly 400 and the driving assembly 200 is connected to the adapter fixing sleeve 310, and the other is connected to the connecting bearing 320, so that the force measuring assembly 400 is limited in the axial direction of the rotating threaded shaft 220.

[0098] It can be understood that the setting of the adapter fixing sleeve 310 and the connecting bearing 320 can convert the rotation + movement mode of the rotating threaded shaft 220 into the mode of only movement of the pulling assembly 500. Specifically, the outer ring of the connecting bearing 320 can be fixed in the adapter fixing sleeve 310, and the inner ring is fixedly connected to the end of the rotating threaded shaft 220 or the end of the force measuring assembly 400, and the other end that is not connected to the connecting bearing 320 can be clamped on the adapter fixing sleeve 310, or can be fixedly connected to the adapter fixing sleeve 310. In one example, the connecting bearing 320 is an external threaded bearing; the end of the rotating threaded shaft 220 of the driving assembly 200 is clamped with the adapter fixing sleeve 310, and one end of the external threaded bearing is fixed in the adapter fixing sleeve 310, and the other end extends out of the adapter fixing sleeve 310 and is fixedly connected to the force measuring assembly 400.

[0099] The specific setting structure is that the end of the rotating threaded shaft 220 is set to be clamped in the adapter fixing sleeve 310 in an inverted T shape, and the external threaded bearing is also set in the adapter fixing sleeve 310, and the rotating threaded shaft 220 is located above the external threaded bearing. The exposed end of the external threaded bearing is threadedly connected with the force measuring component 400. The specific transmission process can be that since the end of the rotating threaded shaft 220 needs to bear the weight of the lower connecting member 300, the force measuring component 400, and the pulling component 500, even if the rotating threaded shaft 220 is clamped with the adapter fixing sleeve 310, due to the large friction force, the rotating threaded shaft 220 can drive the adapter fixing sleeve 310 to rotate together; since the adapter fixing sleeve 310 is fixedly connected to one end of the external threaded bearing, the adapter fixing sleeve 310 can drive the outer ring of the external threaded bearing to rotate, while the part of the inner ring connected to the force measuring component 400 can maintain a state of moving only in the vertical direction.

[0100] Of course, to ensure that the force measuring assembly 400 and below only moves in the vertical direction, as Figure 3 and Figure 4 As shown, in one example, the side wall of the fixed sleeve 110 is configured with at least one guide channel 111, and part of the force measuring assembly 400 is embedded in the guide channel 111. Specifically, two opposite guide channels 111 can be configured on the side wall of the fixed sleeve 110, and part of the force measuring assembly 400 is embedded in the guide channels 111, so as to further limit the force measuring assembly 400 and the pulling assembly 500 thereunder in the vertical direction.

[0101] like Figure 7 As shown, in some embodiments, the support frame 100 also includes support rods 120 arranged on both sides of the fixed sleeve 110, and adjustment wheels 130 movably sleeved on the support rods 120, the two adjustment wheels 130 are used to contact the flexible wire, and the two adjustment wheels 130 are symmetrically arranged about the pulling assembly 500.

[0102] It is understandable that a plurality of limiting holes are provided on the symmetrically arranged support rod 120, and the setting of the limiting holes can adjust the distance between the two adjusting wheels 130 sleeved on the support rod 120 at any time to achieve the purpose of measuring different flexible wires. The adjusting wheel 130 in this embodiment is equivalent to the static guide wheel in the above example, and its main purpose is to provide a fixed value of the flexible wire along the horizontal direction, so as to facilitate the subsequent calculation of the initial preload of the flexible wire. Whether it is pulling the flexible wire or pressing the flexible wire, the two adjusting wheels 130 are located on the same side of the flexible wire, and are located on different sides from the dynamic guide wheel 520 on the pulling assembly 500.

[0103] like Figure 7 As shown, in some embodiments, the pulling assembly 500 includes a pulling rod 510 and a movable guide wheel 520, and the movable guide wheel 520 and the adjusting wheel 130 are respectively located on both sides of the flexible wire.

[0104] Specifically, in the initial state of measurement, it is necessary to ensure that the contact point between the movable guide wheel 520 and the flexible wire, and the contact points between the two adjusting wheels 130 and the flexible wire are in a straight line. If the flexible wire needs to be lifted, the flexible wire contacts the upper surface of the movable guide wheel 520 and the lower surface of the adjusting wheel 130; if the flexible wire needs to be pressed, the flexible wire contacts the lower surface of the movable guide wheel 520 and the upper surface of the adjusting wheel 130, that is, the movable guide wheel 520 and the adjusting wheel 130 need to be located on both sides of the flexible wire, such as Figure 6 shown.

[0105] Fig. 9 is a schematic cross-sectional view of the preload force measurement device according to an embodiment of the present application from another perspective; Fig. 9 As shown, in some embodiments, the pulling assembly 500 further includes a guide wheel shaft 530 , and the guide wheel shaft 530 detachably sets the movable guide wheel 520 at the end of the pulling rod 510 .

[0106] It should be understood that the measuring device provided in this embodiment measures the flexible wire when the terminal device can operate normally. In order to realize the pulling of the flexible wire by the movable guide wheel 520, that is, the flexible wire needs to pass through the gap between the driven guide wheel 520 and the pulling rod 510, the movable guide wheel 520 can be detachably set at the end of the pulling rod 510 through the guide wheel shaft 530. Before the measuring device is installed, the movable guide wheel 520 is removed. When the flexible wire enters the gap at the end of the pulling rod 510, the movable guide wheel 520 is connected to the pulling rod 510 through the guide wheel shaft 530 to realize the pulling of the flexible wire.

[0107] like Figure 7 , Figure 8 and Fig. 9 As shown, in some embodiments, the pulling assembly 500 is connected to the force measuring assembly 400 through a fixed adapter 700. Specifically, a fixed block can be provided at the lower end of the force measuring assembly 400, an inverted T-shaped limiting groove is configured in the fixed block, and a T-shaped protrusion is connected to the upper end of the force measuring assembly 400, and the T-shaped protrusion can be embedded in the inverted T-shaped limiting groove from the side, thereby realizing an effective connection between the pulling assembly 500 and the force measuring assembly 400.

[0108] Fig.10 is a schematic diagram of a calibration structure of a measuring device provided in an embodiment of the present application, such as Fig.10 As shown, the embodiment of the present application further provides a calibration device for calibrating the force measuring assembly 400 of the above-mentioned example measuring device in an initial state, that is, calibrating the initial sensor.

[0109] The calibration device includes a support plate 21, which is configured with a mounting hole; a fixed plate and a fixed pulley 22 are provided below the support plate 21, and the fixed plate and the fixed pulley 22 are respectively located on both sides of the mounting hole. The calibration device also includes a weight 23 and a flexible wire, one end of the flexible wire is connected to the fixed plate, and the other end passes through the fixed pulley 22 and is fixedly connected to the weight 23, that is, the weight 23 is suspended on the support plate 21 through the flexible wire.

[0110] The assembly process is to place the support frame 100 of the measuring device on the mounting hole, and pass the movable and fixed pulleys 22 and the adjusting wheel 130 of the measuring device through the mounting hole to contact the flexible wire. The contact method of the movable and fixed pulleys 22 and the flexible wire can be understood by referring to the above example.

[0111] Since the mass of the weight 23 is known, the tension on the flexible wire is constant. The angle between the flexible wire and the vertical direction after deformation can be calculated by the distance between the two adjusting wheels 130 and the scale mark 600. Then, by calculating the component force of the flexible wire, the resultant force on the flexible wire in the vertical direction can be calculated. The magnitude of the resultant force is the output force value of the sensor. Different magnitudes of the resultant force can be obtained by pulling the flexible wire to different heights, thereby realizing the calibration of the sensor.

[0112] Finally, it should be noted that the above implementation modes are only used to illustrate the present application, rather than to limit the present application. Although the present application is described in detail with reference to the embodiments, a person skilled in the art should understand that various combinations, modifications or equivalent substitutions of the technical solutions of the present application do not depart from the spirit and scope of the technical solutions of the present application, and should be included in the scope of the claims of the present application.

Claims

1. A preload force measuring device for measuring the preload force of a flexible wire, characterized in that: include: Support frame; A driving assembly, movably disposed on the support frame; A force measuring assembly, one end of which is connected to the driving assembly via a connecting piece; a pulling assembly connected to the other end of the force measuring assembly, wherein the end of the pulling assembly facing away from the force measuring assembly is used to abut against the flexible wire; the driving assembly is configured to drive the force measuring assembly and the pulling assembly to move so as to deform the flexible wire; The scale mark is arranged between the driving assembly and the supporting frame, and is configured to measure the distance value that the pulling assembly drives the flexible wire to move, so as to calculate the initial preload force of the flexible wire through the distance value and the force value output by the force measuring assembly.

2. The preload force measuring device according to claim 1, characterized in that: The scale mark includes a first mark and a second mark, the first mark is set on the support frame, the second mark is set on the driving component, and the sum of the numerical value of the first mark and the numerical value of the second mark is the distance value.

3. The preload force measuring device according to claim 2, characterized in that: The support frame includes a fixed sleeve, and the outer side wall of the fixed sleeve is provided with the first mark; The driving assembly includes a differential cylinder, the differential cylinder cover is arranged on the fixed sleeve, and the second mark is arranged at the end of the differential cylinder.

4. The preload force measuring device according to claim 3, characterized in that: The driving assembly further comprises an adjusting knob and a rotating threaded shaft, wherein the adjusting knob and the rotating threaded shaft are fixedly connected, and the rotating threaded shaft is passed through the fixing sleeve and is threadedly connected to the fixing sleeve; The differential cylinder is clamped on the rotating threaded shaft and moves along with the movement of the rotating threaded shaft.

5. The preload force measuring device according to claim 4, characterized in that: The driving assembly also includes a locking nut, which is arranged between the adjusting knob and the rotating threaded shaft, and between the adjusting knob and the differential cylinder.

6. The preload force measuring device according to claim 4 or 5, characterized in that: The connecting member includes an adapter fixing sleeve and a connecting bearing, wherein the connecting bearing is arranged on the adapter fixing sleeve, and one of the rotating threaded shaft and the force measuring assembly is connected to the adapter fixing sleeve, and the other is connected to the connecting bearing, so that the force measuring assembly is limited in the axial direction of the rotating threaded shaft.

7. The preload force measuring device according to claim 6, characterized in that: The connecting bearing is an external threaded bearing; The end of the rotating threaded shaft is clamped with the adapter fixing sleeve, one end of the external threaded bearing is fixed in the adapter fixing sleeve, and the other end extends out of the adapter fixing sleeve and is fixedly connected to the force measuring component.

8. The preload force measuring device according to claim 7, characterized in that: The side wall of the fixed sleeve is configured with at least one guide channel, and part of the force measuring assembly is embedded in the guide channel; And / or, the force measuring component is a tension sensor or a pressure sensor.

9. The preload force measuring device according to any one of claims 3 to 5, characterized in that: The support frame also includes support rods arranged on both sides of the fixed sleeve, and adjustment wheels movably sleeved on the support rods, the two adjustment wheels are used to contact the flexible wires, and the two adjustment wheels are symmetrically arranged about the pulling assembly.

10. The preload force measuring device according to claim 9, characterized in that: The pulling assembly comprises a pulling rod and a movable guide wheel, and the movable guide wheel and the adjusting wheel are respectively located on two sides of the flexible wire.

11. The preload force measuring device according to claim 10, characterized in that: The pulling assembly further comprises a guide wheel shaft, and the guide wheel shaft detachably sets the movable guide wheel at the end of the pulling rod; And / or, the pulling assembly is connected to the force measuring assembly via a fixed adapter.

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